Message Startup Latencies

Table 4.2:
Time for 1 Byte Messages

Wsock

WMPI-C

WMPI-J

MPICH-C

MPICH-J

SM

144.8 s

67.2 s

161.4 s

148.7 s

374.6 s

DM

244.9 s

623.9 s

689.7 s

679.1 s

961.2 s

In Table 4.2 we show the transmission time in microseconds
(s) to send a 1 byte message in each of the environments tested. In
shared memory mode (SM) the mpiJava wrapper adds an extra 94s
(140%) and 226s (152%) compared to WMPI and MPICH C
respectively. In distributed memory mode (DM) the mpiJava wrapper adds
an extra 66s (11%) and 282s (42%) compared to WMPI and
MPICH C respectively. The ``Wsock'' figures are those for a WinSock
implementation of PingPong benchmark using TCP.